| Diluted magnetic semiconductor(DMS) Refers to the Ⅲ-Ⅴ group, Ⅱ-Ⅵ group, Ⅱ-Ⅴ group or IV-VI group compound mixed with magnetic transition metal ions or rare earth metal ions partially replace the non-magnetic cations of a new class of semiconductor materials. Diluted magnetic semiconductors can be prepared the semiconductor device use of the spin in the absence of external magnetic or under help of other magnetic materials, which made the traditional electronic industry faced with a new technique revolution.the Curie temperature of Ideal dilute magnetic semiconductor greater than500K, forming carrier impurity energy band spin splitting and ferromagnetic phase correlation, can choose n or P type doping, high mobility and spin scattering length as well as the magneto-optical effect and anomalous Holzer effect.However, the fact that most dilute magnetic semiconductor’s Curie temperatures far below room temperature, at normal temperature without magnetic cannot be used to make the spin of the electron device. Therefore, to achieve the magnetoelectric integrated spintronic devices must improve the material’s Curie temperature. At present, the diluted magnetic semiconductor research main problem is how to produce more kinds of materials and to find more suitable for a wide range of doped elements to improve the Curie temperature of diluted magnetic semiconductor. The main content of this paper is in the group IV semiconductor material Si doped magnetic transition metal Mn.In this paper, we studied the use of magnetron sputtering deposition of Si quantum dot films and doped Mn, and using a tubular furnace in Ar gas protection on the sample temperature diffusion treatment, obtained by different annealing conditions sample. And by scanning electron microscopy (SEM), atomic force microscopy (AFM) on the surface of the sample topography variation with temperature were studied; by X ray diffraction (XRD), infrared spectroscopy instrument and X ray energy spectrum (EMAX) and other means for the characterization of samples on the microstructure and composition, understand the annealing influence of microstructure of samples; current-voltage (Ⅰ-Ⅴ) and the Holzer effect method to analyse the sample electrical properties affected by the effect of annealing temperature situation; finally, by using a vibrating sample magnetometer for measuring the magnetic hysteresis loops, clear sample magnetic characteristics. This thesis sample substrate for P-Si (100) substrate.The sample morphology observation, annealed before the sample surface is compact and uniform, no clusters of small particles, after annealing for two kinds of elements in the sample surface thermal diffusion, emergence of particle size in20nm around the small clusters, by EMAX on the element analysis that these small clusters may be SiMn alloy phase, in addition Mn also has entered the part Si lattice. XRD tests tell us annealing changed the structure of the sample, the film appeared SiMn second. Infrared transmission spectra show high temperature annealing can change the optical properties of SiMn thin films. Current voltage (Ⅰ-Ⅴ) and the Holzer effect, the electrical properties of samples was presented with the relationship between the change of diffusion temperature, diffusion temperature is higher, better electrical performance. From the vibrating sample magnetometer measured hysteresis loops that preparation sample with higher than room temperature magnetic, analysis these magnetic group from the previous SEM observed inlaid in the film of SiMn alloy particles. |
PDF Full Text Request